It is known that a combination of nitrites and amines may produce nitrosamines, some of which are believed to be carcinogenic. This problem is acknowledged by the persons skilled in the art and efforts have been undertaken to prevent the formation of nitrosamines. For example, in U.S. Pat. No. 4,200,542 it is described that the inhibition of nitrosamine formation can be obtained by adding to the grease composition a combination of an ascorbate or iso-ascorbate with alpha tocopherol. Although the latter combination is claimed to be effective, it is evident that only grease compositions that do not contain nitrites and/or amine derivatives can adequately solve the problem of nitrosamine formation.
European Patent Application No., 0084910, Application No. 832000772 filed Jan. 18, 1983 discloses a grease composition containing lithium salts of carboxy mono-acids and diacids. The Li-greases may contain Ca or Mg alkyl salicylate, which salicylate may be either neutral or overbased.